The present invention relates to a vehicle body of a shell type construction, and to a method for producing the vehicle body.
Various self-supporting vehicle bodies of a shell type construction (also: sheet-metal shell type of construction) are known from the prior art. A characteristic of the shell type of construction is that the various constituent parts of the body, such as for example the roof frame, the individual pillars or the sills are, in each case, assembled from an upper shell and a lower shell. The assembled upper and lower shells form a closed profile with a cavity. The upper and lower shells are also referred to as outer and inner shells.
It is an object of the present invention to provide a vehicle body of shell type construction which, while being inexpensive to produce and assemble, is operationally reliable, durable and of lightweight construction. It is a further object of the present invention to provide a corresponding method for producing the vehicle body.
This and other objects are achieved by way of the embodiments according to the invention.
In a first aspect of the invention, a vehicle body of shell type construction includes a rear frame extending in a vehicle transverse direction. The rear frame extends transversely over the width of the vehicle at the rear, for example between longitudinal members or between the rear pillars (C pillars). A lock counterpart is normally integrated in the rear frame. The lock of the tailgate engages into the lock counterpart. Furthermore, the rear frame normally serves for the connection of the rear bumper. The rear frame is assembled from a so-called supporting rear panel and a rear panel. The supporting rear panel is in the form of an inner shell, and the rear panel is in the form of an outer shell. The inner and outer shells form a closed hollow profile, as is conventional in the case of the shell type of construction for vehicle bodies.
It is provided according to the invention that the supporting rear panel, that is to say the inner shell of the rear frame, is assembled from a central part and at least two side parts. Thus, according to the invention, the supporting rear panel is in at least three parts. The central part is formed as the lock counterpart for the lock of the tailgate. The multi-part form of the supporting rear panel makes it possible that, in the region of the lock counterpart, the rear frame is assembled from the central part and the rear panel only. There is no need for doubling-up of metal sheets or for other reinforcement elements, such as for example partitions, within the rear frame in the region of the lock counterpart. By virtue of the fact that, according to the invention, the separate central part is provided, the central part can, independently of the two side parts, be configured such that it is stable enough to function as a lock counterpart. A further advantage of the multi-part supporting rear panel is that the components, and thus also the tools required for the same, are smaller. The central part can be constructed and produced independently of the side parts. In this way, it is possible for the material, the material thickness and the geometry of the central part to be configured in accordance with the requirements for the lock counterpart.
Provision is preferably made for the central part to be formed from a thicker material, in particular a metal sheet with a greater sheet-metal thickness, than the two side parts. Owing to the multi-part form, according to the invention, of the supporting rear panel, it is possible for a relatively thick metal sheet to be used only in the central part.
It is furthermore preferably provided that the lock counterpart is a lock striker formed in the central part. The lock striker serves for the engagement of the lock of the tailgate. In particular, the lock striker has, in the prior art, been reinforced by doubling-up of sheet metal. According to the invention, this is no longer necessary, as the central part can, by means of a corresponding geometry or corresponding materials, be constructed independently of the side parts.
For the connection between the side parts and the central part, there are two preferred variants: in the first variant, the central part may overlap the respective side part. In this way, adhesive bonding, riveting and/or welding of the two parts is possible. Here, use is made in particular of spot welding. In the second variant, the side parts may be butt-welded to the central part. The term “tailor welded blanks” is also used in this context.
It is particularly preferably provided that at least one of the side parts overlaps the central part. Specifically, in this way, an adjustment of the total length of the supporting rear panel in the y direction (vehicle transverse direction) is possible. This adjustability in the y-direction permits an expedient connection of the supporting rear panel, at its lateral ends, to further constituent parts of the vehicle body. In particular, the outer ends of the side parts are in each case connected to a longitudinal member, to a luggage compartment and/or to a rear pillar (for example the C pillar) of the vehicle body. This fixed connection of the supporting rear panel at both sides is possible only if the total length of the supporting rear panel is variable during the assembly of the vehicle body.
The central part is preferably manufactured from a thicker material than the side parts. As a result, the central part tends to be heavier than the side parts. It is therefore preferably provided that the central part is designed to be as small as possible. A central part length is defined in the vehicle transverse direction (y-direction). The central part length is, in particular, at most 50 cm, preferably at most 40 cm, and particularly preferably at most 30 cm.
The two side parts and the central part are preferably produced from shaped or formed metal sheets.
The invention furthermore encompasses a method for producing the vehicle body. Here, the method includes the following steps: firstly, the parts of the supporting rear panel are provided. The supporting rear panel forms an inner shell of the rear frame. As already described, the supporting rear panel includes a central part and at least two side parts. A total length of the supporting rear panel is defined in the vehicle transverse direction (y direction). In the following step, the connection of the two side parts to the central part, and the connection of the two side parts to further constituent parts of the vehicle body, are performed. The further constituent parts of the vehicle body are, in particular, longitudinal members, a luggage compartment, or rear pillars (for example C pillars). The side parts are thus fastened in each case by way of their inner ends to the central part. The outer ends of the side parts are connected to the further constituent parts of the vehicle body. According to the invention, before the connection at least of the final side part to the central part, an adjustment of the total length of the supporting rear panel is performed. In this way, it is possible for the side parts to be able to be fixedly connected without a gap, or with a desired gap dimension, to the further constituent parts of the vehicle body. In particular, it is provided that at least one side part overlaps the central part, such that the adjustability of the total length is possible in an expedient manner.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.